Waterlines within dental units are heavily contaminated with microorganisms and have been identified as a source of hazardous microbial exposure for patients and health care providers. The American Dental Association is requesting water quality improvement and water quality monitoring. The aim of this proposal is to demonstrate safety and efficacy of a system which is designed to improve the microbiologic quality of water used in dental treatment. The efficacy of Enzodine for use in the disinfection of dental waterlines was demonstrated in Phase I. Enzodine, a disinfectant which is biocidal against bacteria, fungi, viruses, and bacterial and fungal spores, was found to effectively prevent formation of bacterial biofilms and to reduce artificially generated bacterial biofilms in dental waterlines. Additionally, Enzodine performed favorably in preliminary biocompatibility and materials compatibility testing. Phase II studies are designed to further develop Enzodine as a simple, inexpensive method of maintaining a safe environment for patients and dental personnel. Studies will involve (1) testing Enzodine in clinical settings as a disinfectant for dental waterlines, (2) performing additional materials compatibility testing with the metal, rubber and plastic materials contained within dental units, (3) performing additional biocompatibility studies, and (4) testing the prototype delivery system in clinical settings. PROPOSED COMMERCIAL APPLICATION There are approximately 400,000 dental units in the United States, virtually all of which contain significant microbial contamination. Our system will provide a simple and inexpensive method of maintaining an acceptable and safe environment for patients and dental personnel. It can be attached to any existing dental unit, and can be incorporated into manufacturing processes for new units. In addition to the U.S., there is a much larger worldwide dental market. This technology also has potential applications in other industries in which biofilms are a major problem.